Production of iron and steel



AH. :ist: Il--.

f :Nwmww'mmmmqwwl Filed Mam 26, 1920 Patented Apr. 8, 1924.

UNITED NSTATES resem PATENT OFFICE.

.ARTHUR J'. MOXHAM, 0F GREAT NECK, NEW YORK, ASSIGNOB, BY MFSNE .ASSIGN-'l MENTS, TO J. I. LA FFEY, TRUSTEE, OF TI\..MIING 'I0N, DELAWARE.

PRODUCTION 0F IRON AN D STEEL.

Application led latch 26, 1920. Serial No. 368,859.

To all whom t may conce/rn.'

Beit known that I, ARTHUR J. MOXHAM, a subject of the King of GreatBritain, and a resident of Great Neck, in the county of Nassau and Stateof New York, have invented new and use-ful Improvements in theProduction of Iron and Steel, of which the following is a specification.

My invention relates to the production of iron and steel, and has forits general object the provision of a more economical and uniformlyeiicient method for obtaining iron and steel of the desired quality andcomposition, and especially the very highest grades of steel, byoperations conducted on a large scale.

To this end I have invented a complete process which includes everyessential step eginning with the treatment of the iron ore and endingwith highly urified steel of any desired composition. here are alsoinvolved in this invention novel sub-processes directed to the samegeneral end and which I prefer to employ as parts of myvcomplete processbut which may with advantage be employed independently thereof. For thepractice of my invention, I have also devised certain apparatus whichwill constitute the subject matter of one or more se arate applicationsfor LettersPatent an which is not illustrated or described in detail inthe present application, but only in such general manner as will bestaid an understanding of my process and its several advantages.

My complete process generally described includes the leaching of ironore with asuitable acid, preferably sulfuric acid, whereby the iron inthe ore becomes a salt in Solution such as ferrie sulfate, theseparation of the solution from the gangue, the conversion of ferriesulfate or other iron salt to an oxid of iron, preferably ferrie oXid,and the subsequent reduction and purification of the ferrie oxid orother ctids of iron and the addition to the iron of suchingredients asmay be needed to secure the desired reactions or as may be desired inthelinal product iu the case of ferro alloys.

Bothr the process as a Whole and the several steps thereof have beendevised -with specific purposes inmind, which will 'appear in connectionwith the `description herein ofone specific embodiment of my invention,but among which ma be mentioned the saving of heat energy, tli

e production of a Vhigher grade of steel than has heretofore beenpossible when made uniformly and by large scale operations, and theconservation for re-use in the most economical mannerof reagentsemployed in carryingon the process. The economy of heat energy isobtained by my process (l) because I avoid the necessity4 of bringing toa high heat the silica and other impurities of the ore, the heating offluxes therefor, and the melting of a large quantity of slag, and itsremoval Vfrom the molten steel, (2) because I utilize the heat energy insuch manner that-progressive changes of the material necessary to itsreduction and purification are accomplished at temperatures and underconditions most practical for etlicient action, whereby the materialneed not be maintained at higher temperatures as long as would otherwisebe the case or maintained at lowertmperatures an unduly long time, (3)because I am able to conserve to a high degree the heat energy developedat certain stages of the process for use atother stages thereof, and (4)because I am able to recover from the'smelting operation a much largerportion of deoxidizing and combustible gas than is the case in knownsmelting operations. The uniform production in large quantities of asuperior high grade steel is made possible in my process because littleor no slag becomes mixed with the molten metal and because in therelatively low temperature steps ot the process the iron is so farpurified that the re# actions occurring at the relatively hightemperature steps are simpler and more quickly accomplished than is thecase when a number o re-actions at the same stage of the operation mustbe depended upon, as in the case of refining at these high temperatures.The avoidance of the Waste of reagents is effected in my process largelybecause I em- Vploy V1re-agents which may be readil lreorme'd and thenused again, instead of eing practically consumed as, for example, is thecase when luxing the im urities of the ore with limestone in a blasturnace.

The drawing accompanying this applica tion is a diagram of the severalsteps of the complete process, showing the successive stages in thetreatment of the iron contain wil ing material, the 4,recovery of theleaching acid and the circulation and utilization of the gases.

I shall describe my invention on the as- 55 separate operation,

Ythe sulfate into the same sumption that the more usual iron ores are tobe employed, namely: ores in which the iron is in the form of an oxid,but in any case silica and other impurities in the accompanying gangueconstitute a considerable portion of the ore. The first step, afterpreferably crushing the ore to a suitable tineness and the eliminationof the adherent clay or dirt in any suitable way, is to subject largebodies of the ore to the action of a suitable acid-'cf suitable strengthand under such conditions as will most efficiently convert the iron'inthe ore to a salt carried in solution. I prefer to use sulfuric acid forthis purpose, because I desire to convert the .iron to ferrie sulfatewhich may be economically decomposed by suitably applied heat intoferrie oxid, suitable for reduction and refining, and sulfur trioxidgas, suitable for the commercial production of sulfuric acid for theleachin of fresh ore.

I pre er to employ the specific process of leaching with sulfuric acidinvented by Albert W. Davison, which process will constitute the subjectmatter of an ap lication for Letters Patent of the United tates by him.In accordance with that process, the

ore is leached in sulfuric acid of such specific gravity-and at suchtemperature as to maintain theferric sulfate in solution until after thesolution is entirely separated from the gangua The gangue should also beWashed suiciently to recover in solution all ofthe ferrie sulfate formedin the leaching process `in concentrated form. The ferrie sulfate soreclaimed from, the gangue is then,y

crystallized from the' solution.

In the diagram I have indicated at the left a body of iron ore and thatit is brought to the leaching apparatus. I have indicated, by the firstsquare at the left, the treatment of the iron ore thus far described,whereby its iron is converted into ferrie sulfate [Fe2 (504),] andseparated from the other imuritles contained in the ore that areinsolule in sulfuric acid. At this point the Agangue'fia separated outand I have no furmy present proc;v ess is concerned. The diagram showsthat" ther interest in it, so far as the ferrie sulfate is carried.forward to the next stage of the process, which comprises the'conversion of the ferrie sulfate into ironA oxid, preferably ferrieoxid (Pozos).v It is/ preferable that this decomposition, Whethercomplete or partial, should take place as a rather than to introducefurnace as the one Where the melting of the iron occurs, even thoughthis furnace may be depended on to complet-e or make perfect the finaldeoxidation. In my process, therefore, the next stage of the operationis, as indicated in the diagram, to convert the ferric sulfate intoferrie oXid (FegOs) and, to effect this, I prefer to adopt themethodwhich will also oXid and sulfur trioxidgas.

be described in the aforesaid Davison application, to Wit: Thedecomposing of the ferrie sulfate by the direct application of heatedgases While the particles of the sulfate are thoroughly agitated as, forexample, by the employment of the Well-known I' 7edge furnace, to ensurethe rapid and effective application of heat throughout the ferriesulfate. It has been found that no interference of any kind occurs Withthis action, if hot carbon monoxid gas alone, or admixed with carbonioacid gas and nitrogen, is brou lht in direct conta-ct with the articlesof erric sulfate. I have indicated in the diagram that at the stage ofthe process now under consideration hot carbon monoxid gas andthecrystals of ferrie sulfate are brought together and result in thedecomposition of the ferric sulfate into ferrie The ferrie oxid is inthe form of a fine'reddish powder and contains practically all the ironthat was in the iron ore.

This ferrie oxid is next, as indicated on the diagram, more or lessdeoxidized and considerably changed in its mechanical formation by beingsubjected to intimate contact with a hot reducing vas, preferably carbonmonixid gas. If tiegas at this point should sometimes happen to not berich in carbonI monoxid, it is onl necessary to charge lin and mix Withthe erric oxid some powdered coke or other form of carbon-or otherreducing agent. For this purpose, I again prefer to use the Wedge typeof fur nace so that the ferrie oXid will be violently agitated andbrought into the most intimate relation with the heated as, whereby therapidity of the action wil be greatly increased. ,The gas should be ofhigher temperature than that employed in decompoa ingthe'ferric'sulfate, but the deoxidation and the conglomeration of themore or less deoxidized material are affected both by temperature andduration of treatment,

'complete deoxidation of the ferrie sulfate may be effected at thisstage of my process, the degree ofdeoxidation .stage is sometimes ofless practical importefected at this ance than the conglomeration of thematerial to the proper degree to permit of the l easy passage of thegases used in the next stage of my process. Furthermore, the teniperature at this stage of the process is relatively low and it willordinarily be found more economical to eliminate the last of the oxygenfrom the iron oxiz'd at the@ higher temperatures `which areVemployer/lain the next stage of my proce where'this final deoXida-tionis performed efliciently rapidly.- On the other hand, if desired, thepresent stage of the process could be omitln this subsequent stagedeoxidation of the more or less deonidized iron is completed, the ironmelted, and carbon monoxid produced. This is accomplished by 15 ess withcarbon preferably 1n the form of powdered coke in proper proportions toproduce the desired results, the mixture being fed to the up r end of acolumn of said materials an materials produced therefrom and acted u onto produce the desired deoxidation, melting and production of carbonmonoxid as the iron containing material-or iron and carbon pamldownwardly through the column. This `lstage of the v4 process may becarried on in 'a furnace which is generally similar to the ordinary ironcupola but which is arranged to have the down-draft now to bedescribed.' Air and a reducing gas, such as carbon mononid, aredelivered to the upper part of the column as shown in connection withthe rectangle at the right hand end of the diagram, and forceddownwardly through the column ofmaterial, thereby establishing at theupper end oi the column a zone in which the more or less deoxidized ironcontinues to he deonidized to iron by the carbon moncnid and inwhich'carbon dioxi/d is duced. The air admitted at thetop of the columnis preferably just suiicient to' combine with the carbon tdproduce theheat needed for the deoxidizing reaction. The temperature in this zonegradually increases from the top of the column downward to perhaps atemperature of 700 to 800 C. Ablut no melting occurs in this zone.

:duced in the said zone, still mixed with carhon, that has not been usedup in the upper ft/zone, is subjected to a much higher tempen.

ature to melt ythe same. This iron melt wardly through the column yormaterial from a peint between thedcoaidizingand j melting sones asuitable quantity of air forA eiiective combustion of the carbon to de-Avelen the desired high temperature. At' 'this high temperature. suchcarbon dioxldas may enistin the iron melting zone is con, *rented` by.-Ycombinarion yvith incandescent mixing the more or less deoxidized irontained in the preceding stage of the proc-'' Below the deoxidizing zone,the iron pro.

inganna is established by forcing doWnA-f.

downward toward the melting zone; so that the material acted upon iseffectively carried to this zone and danger of blowing the material outof the upper end of the column and thereby wasting it is avoided, thisbeing especially important ify it is introduced to the cupola in afinely divided or powdered state. This method is accordlngly, asheretofore stated, especially well adapted to operate elliciently uponline powder, such as the ferrie oxide produced as described above. Thisstage of my process is one capable of advantageous use in 'connectionwith manufactures other thanl that of iron and steel, both because ofthe advantage that the draft tends to bring all materials towards themelting f or most highly heated zone and lbecause it effectivelyconverts carbon dioxid gas into carbon monoxid gas, the production ofwhich gas ishighly useful in the practice not only of my process butalso for other commercial processes and purposes.y

The iron now containing some carbon, as s own by the heavy line andsmall rectangle at the lower right hand side of the dia ram,

flows as it melts into a suitable re ning hearth where it is purifiedand where suitable ingredients are, if desired, added to flpduce a steelof any desired composition.

e melted iron is maintained in this retin ing hearthin a fluidcondition'.

the refiningr hearth preferably corresponds :approximately to suchtemperaturesas are Vturn may depend upon whether the steel produced inthe refining hearth is to be used without further refining `or change,or

whether, prior to casting. it is to be. subi .,jected -to furtherrefining ata higher tem .,perature, as hereinafter described.

.it is always possible by increasing the amount of coke in the cupolaand the amount oit" air forced into its lower zone to increase thetemperature et the refining. hearth containing the molten metal. At thisstage or' the process, any method `rit/treatment for purifying or a dingingradients hnown to steel makers, including especially those egloyed inthe cpenhearth process may be u The iron entering the refining hearthwillcontain carbon prefer# ably in licrcess of that desired in the nalsteel "and the hath is partially denar- 'ghonizcd inthe reininp hearth.

purpose l prefer to some et 'dared ferrie oxidproduced at the learlierFor this the powstage of the process, or else depend upon a `vbasiclinin in tha retiring hearth, or both.

Suitable eat for the material in the retining hearth may be provided inany suitable lhe temperature Vof the molten bath in y lll@ 'liti irai 'ing forehearth.

Way, but I prefer to. direct the very hot carbon monoxide gas producedin the preceding stage of my process into the hearth above the moltenbath, as indicated by the dotted line in the diagram. It a temperaturehigher than the sensible temperature of this gas is desired, air may beintroduced into the refining hearth so that a art of the carbon monoxidemay be burne as the gas passes through the refining hearth to producethe additional heat required. The method of reducing Ithe iron oxide andrelining the metal described above is more eficient than those nowemployed. In the latter methods, the purification is largely a matter ofbatch action in which the elimination of the Whole of a given impurityis effected at nearly the same time throughout the Whole charge. In myprocess, various actions are taking place simultaneously 4throughoutdifferent parts of the material being treated. While iron oxide is beingreduced at one point, and iron is being melted and carbonized atanother, the melted metal Hows very slowly, in small particles or evenin drops, into the purify*- Here it reaches a mass of the purifyingagent, and during a large part of the operation it also meets a largemass of met-al already purified. V The purification of the metalentering the refining hearth is practically instantaneous because of thefact that it enters continuously in minute streams or drops whichimmediately react With the layer of slag in the refining hearth. In thisrefining hearth the metal is collected until there is sufficient for anordinary casting operation, or for removal to the electric furnace if itis to be further refined. In either case, it is a matter of choicewhether when the metal is poured from the refining hearth it is firstemptied completely or,'instead, left therein as a nucleus for collectionof the next batch. Because of the fact that during the collection of themolten metal in the refining hearth the purification is taking placecontinuously in the small quantities flowing into the hearth, amplenotice is given of any adverse conditions and, therefore, there is ampletime to remedy them. Thus, if an analysis should show a small rise ofsome impurity in the molten bath, it becomes evident that a much moreimpure metal has been entering the bath and that some operatingconditions must be changed, although lthe impuremetal has' been sodiluted that as yet no substantial harm to the metal as a whole has beendone.

Furthermore the reversible reactions commonly encounteredare obviated,and the reactions are more stable than heretofore.

he final purifying actions are continuous and a number of differentactions are simultaneously taking place.

My process is also one of increased efficiency in operation and in theresulting product, because of the small amount of Slag produced at anystage of the process, owin to the veryvcomplete separation of the silicaand gangue and also of the manner by which whatever slag is foundbecomes later separated from the metal bath by settlement. The extent towhich the particles of slag included Within the steel afects the qualityof the steel has become better understood Within recent years, and steelmakers have been giving greater attention than heretofore to the removalso far as possible of every particle of slag from the molten bath beforecasting the metal. The removal of the slag, however, from a lar e batchof molten metal is extremely di cult requiring that`the bath bemaintained at a high temperature for a long period of time. In myprocess a very small amount of slag is formed because of the fact thatthe usual impurities of the iron ore have been largely removed,particularly the silica. Practically the only silica present is thatderived from the silicates in the coke and these can be kept at aminimum by proper Washing of the coal previous to the coklng o eration.The small quantity of slag pro uced is, moreover, formed in such mannerthat it is readily separated from the metal as it enters the orehearth.The materials melting in the bottom of the cupola drops in tiny streamsor even drops, to the floor of the cupola an then pass to the bath ofmolten metal in the forehearth so that the very -minute quantities ofslag that accompany such drops of metal easily separate therefrom andhave no tendency to become mixed with the bath of molten metal.Moreover", the relatively large mass of molten metal in the forehearthis maintained hot for a considerable period by the gases facilitatingthe further separation of the heavy metal from the lighter slag.

The production of steel with practically no slag is an important resultof my invention.

When the very highest grades of steel are desired, the molten steel is,with my process, then subjected to electric heat-ing in order to givethe molten bath the very high temperatures which are at present'I onlyobtainable in the electric furnace. The diagram indicates that after thepurifying stage, the molten steel is subjected to electric heating. Asthe results generally obtained in an electric furnace are Well known andthe various methods of treatment therein known, I do not need to detailtl'em, it being understood that the length of time during which the bathis subjected to this electric heat and the particulan heat treatmenttherein must depend upon the exact character of steel desired, as wellas upon the particular treatment which the steel has received m theforehearth.

tric furnace is relatively expensive and that the length of time towhich the metal must be subjected to this costly heat, in order thatsteel of some definite desired purity 4may be..

obtained, is dependent mainly upon the degree of previous purificationof the steel and its temperaturewlien `it reaches the electric furnace.

reasons above stated, it will be already so highly purified that it needbe maintained only for a relatively short periodin .the

electric furnace, iiiorder to remove the last traces of undesiredingredients, particularly the sulphur, the slag and occluded gases.

l therefore reduce the expensiveI electric heat-ing to a. minimum. Whileobtainin a product of the very highest grade,.and t us.

am enabled to effect a wider commercial eniployment of electric heatingthanhas heretofore been possible, and ak Wider use'of the very high`grade steels.

As shown by the dotted line on the diagram, the very hot carboninono'xid from the melting zone, after passing through the purifyingforehearth may be, and desirablyr is, employed as the reducing agentforthe preliminary partial deoxidation of the fer: ric oxid. During thisaction, a part ofthe carbon monoxid is converted to carbon .di-.4..oxid. The sensible heat. of the fiemaining hot carbon monoxid (with thecarbon di,

through a heater to heat-the latter, and I have shown the heaterutilized to heat the sulfuric acid to assist in bringing it to thedesired temperature for leaching.

The sulfur trioXid produced as described above is converfedinto.sulfuric acid,fwliich after passing through the heater is used for,leaching the ore., as shown bythe light solid.

line in the diagram. For this purpose,the carbon monoxid, carbon dioxid,and sulfur` trioxid from the heater may be passed througla. suitablecondenser, the sulfur tri-l oXid ng converted into sulfuric-4 acid,which is condensed, and the other gases passing on and beingvdesirablystored in a suitable reservoir, as shown. reservoir the gas, which hasnow becomev cool, may be drawn for use in the final deoxidation of theiron oxid. By my process,

there is thus provided a` continuous supply' I call attention, hoivcver,to the fact that heating in an elec In the 1practice 'of my 1 process,the steel will not only-be molten` when it reaches the electric furnace,but, for'-` From this cf reducing gas andtlieheat of `thesaine, is,A

advantageously utilized.

,Moreoven it shouldbe noted that more or i less rich gas v(containing nocarbon. dioxid) is available and is regulated ,according to the ,need bythe Vamount ofcole charged and thet amount `ofair supplied.

4As the inert nitrogencarried into. theis'ys` teni withthe-airaccumulates, the .gases g should. from' timev to timelee-,allowed to escape to the air anda freshwzsupply ofc/rich gas proiiluced. y :It .is to be understood that .thespecic process .describedisv merely r4illustrati:veof

my invention, and thatl changes Within theI scope of the appendedclainisinay beinade without depart-in 4from theinventiom For example',Whil'eltiense of .the doivnfdraft,

smelting operation .herein .,descr,ibed. is aA very limportantspecific,feature ef. vmy coinf, plete process, and is-alsou-seful independ--.ently thereof, yeti-.my invention hroadly "con,- i sidered includes thecombination with other stepsY of my process of any,known-method. forcompletely, deoxidizing the .iioiif-oxide and meltingtlie'reduced iron..n.

Having described. my invention, what I, claim as newfand desire.r tosecure yby Let l. The. processi ofe'X-tracting iron from its ores` whichcomprises treating tliegkore with an acidtodissolvethe iron as l.anironsaltand separate it lfrom the.silici ous-por tions of theore, convertingthe ,separated iron salt into yani'ronlortid, 4and reducing the 2.Tliaproces's of extracting-iron -froniits ores. which tom-prises-treating the 4iron ore, to i convert the iron thereinl to ferriesulfate and separate it from the silicioiis ingredients o'f theore,-converting the ferrie sulfateto an iron oxid and'then reducing theoii.d. Y g.; v 3. The method .ofproducing ironwyhieh consists in firsttreating a vsilicious mineral containing iron with sulfurie'acld`to.produce sulphate of'iion .in solution, separating the,l solutionfrom ,the undissolved matter, then` acting .upon Athev salt tof againproduce iron oxid, and then reducing the oXid hy snielting operations.VA y iron :ores which `includes .act-ing upon theiron ore to convertv theironmtnerein to a salt in' solution, then separating .the soin tionfrointhe'nndisselved portionoftlie ore,

then acting u-pcnvthe salt to againpreduce iron ioxid and then :reducingthe. oXid by smelting-operations` :'SfTheprocess of producing iron fromsilicious-` minerals containing ferrie Voxid.

Which includes first actingJ upon the mineral to produce ferricsnlphatein solution, then separating the solution from the undissolved mattei',then decomposingthe ferric sulphate'v by lheat to lagain'produce ferrieoxid, and

ico

c vne ,4. The process of producing, iron from 'then reducing the oxid bysmelting operations. Y

G. The process of producing iron from iron ores which includes firsttreating the ore with sulfuric acid to produce ferrie sulphate insolution, then separating the solution from the undissolved matter, thendehydrating the ferric sulphate, then calcining 'the ferrie sulphate todecompose it and produce ferrie oXid, and then reducing the oxid bysmelting operations.

T. The process of extracting iron from its ores which comprises leachingthe ore with sulfuric acid to produce a solution of ferric sulfate,separating vthe solution from the undissolif'ed part of the gangue,cmiverting the ferrie sulfate to iron oxid, partially deoxidizing theiron oxid with a gaseous reducing agent while agitating the oxid tofacilitate the action of the reducing agent thereon until a suitablepartially deoxidized iron sponge is produced and thereafter furtherdeoxidizing the iron sponge without agitation and at a materially highertemperature. l

8. The process of extracting iron from its ores which comprises treatingthe ore to oonvert the iron therein into ferrie sulfate and to separateit from the silicious materials of the ore, then converting the ferriesulfate to iron oxid, then partially reducing and conglomerating theiron oxid, then mixing the conglomerated material with carbon andcompleting its deoxidation in the presence of a reducing gas and withpartial combustion of the carbon, then meltincr the iron with furthercombustion of the caibon, then collecting the metal as it melts to forma bath continuously subjected to heat, and treating the bath withsuitable agents to produce iron or steel of a desired composition.

9. The process for obtaining iron or steel from iron ores comprisingconverting the iron contents of the ore into ferrie sulfate andseparating it from the silicious contents of the ore, then convertingthe ferrie sulfate into an iron oxid powder, then agitating this powderin the presence of a stream of hot carbon monoaid to cenglemerate andpartially deoxidize it, then mixing the conglomerated material withcarbon and completing its deoxidation in the presence of a reducing gasand with partial combustion of the carbon. then melting thel iron withfurther combustion of the carbon, and then collecting the. metal as itmelts to form 'a bath continuously subjected to heat, and treating thebath withsuitable agents to produce iron or steel of a desiredcomposition.

10. The process for obtaining iron or steel from iron ores comprisingconverting the iron contents of the ore into ferrie sulfate andseparating it from the silicious contents of the ore, then convertingthe ferrie sulfate to an iron oxid, then more or less deoxidizing theiron oxid, with carbon monoxi'd. then mixing the material thus producedwith carbon and adding the mixture. to the top of a column of material,the upper part of which is subjected to a downward draft of carbonmonoxid gas and sufficient air to produce a progressive heatingand thelower part of which is subjected also to a further down draft ofsutiicient air to effeet a melt-ing temperature, collecting the metal asit melts in a bath subjected to the heated gas issuing from below themelting zone of the column, and suitably treating the molten bath.

11. The process for ol'itaining iron or steel from iron ores comprisingconverting the iron contents of the ore into ferrie sulfate andseparating it from the silicious contents of the ore, thenvconvertingthe fcrric sulfateA into an iron oxide'powder, then agitating thispowder in the presence of a stream ofl adeoxidizing medium toconglomerate and partially deoxidizethe iron oxid, then mixing theconglomerated material with carbon and adding the mixture to the top ofa column of material, the upper part of which is subjected to a downwarddraft of carbon monoxid gas and sufficient air t0 pro- -duce aprogressive heating below melting temperature and the lower part ofwhich is subjected also to a down draft of sufficient air to effect amelting temperature, collecting the metal as it melts in a bathsubjected tothe heated gases issuing from the melting zone of thecolumn, suitably treating the molten bath, and finally subjecting themolten metal to electric heating.

12. The process which comprises conglomerating and partially deoxidizingan iron oXid with a gaseous deoxidizing agent while agitating the oXidto facilitate the action of the deoxidiziug agent thereon` andthereafter'further deoxidizing the conglomerated material at amateriallyhigher temperature produced by combustion in the mass of said material.

13. The process which comprises convertn ing the iron of iron ore toiron oxid in the form of a fine powder, partially deoxidizing the ironoXid powder with a gaseous deoxidizing agent while agitating the oxid tofacilitate theaction lof the deoxidizing agent thereon, and thereafterfurther deoxidizing the material at a materiallyhigher temperatureproduced by combustion in the mass of said material.

14. The process which comprises conglomerating and'partially deoxidizingan iron oxid with a gaseous eoxidizing agent, heat for the partialdeoxidation being supplied by the sensible heat of deoxidizing agent,and thereafter further deoxidizing the conglomerated material with theap- IBG iti

plicatioii of heat obtained by combustion of carbon.

15. rllhe process which comprises feeding a mass of material includingan iron oxid in a given direction into a melting zone, and forcing adeoxidizing gas into the mass at a point remotey to the melting zone andleading the gas away after it has passed through said melting zone.

16. The process which comprises forcing a deoxidizing gas downwardthrough a column of iron containing material including an iron oxid toestablish an upper zone for deoxidizing the iron oxid, establishingbelow said zone a zone for melting the deoxidized material, and leadingthe gas awa after it has passed downwardly througi said melting zone.

17. The process which comprises forcing a gas comprising carbon monoxidinto av column of iron containing material including an iron oxid todeoxidize the iron oXid and convert carbon monoxid to carbon dioxid,adding air to the column to form an iron melting zone, reconverting thecarbon dioxid to lcarbon monoxid, and leading the carbon monoxid awayafter it emerges from the melting zone.

18. The process which comprises forcing carbon monoxid and air inregulated pro,

portions into the upper portion of a column of iron containing materialincluding an iron oxid and carbon to establish an upper zone fordeoxidizing iron oxid, admitting air at a lower level to form a meltingzone below said .upper zone, reconverting to carbon monoxid in saidmelting zone carbon dioxid produced above said melting zone, and leadingthe carbon monoxid away after it emerges from said melting zone. y

19. The process which comprises establish- Aing a column of ironcontaining material and progressively increasing the temperature thereoffrom the top, forcing a current of deoxidizing gas downward throu li thecolumn to deoxidize the iion oxid, me ting the deoxidized iron,deoxidizing tlie oxidized gas, collecting the metal as it melts to forma bath, and purifying the molten bath while subjecting it for a suitableperiod f time to the heat of said deoxidizied gas. 20. The recess whichcomprises establishing a. co umn of iron containing material andprogressively increasing the tempera- -ture thereof from the top,forcing a current of deoxidizing gas downward through the column todeoxidize the iron oxid, meltini the deoxidized iron, deoxidizing theoxidized gas, collecting the metal as it melts to form a bath, purifyingthe molten bath while subjecting it for a suitable period of time to theheat of said deoxidized gas, and further purifying the molten bath bymeans of electrically generated heat.

21. The process which comprises establishing a column of iron containinmaterial and'progressively increasing tie. temperature thereof from thetop, forcing a current of deoxidizing gas downward through the column todeoxidize the iron Oxid, ine ting the deoxidized iron, deoxidizing theoxidized gas, collectin the metal as it melts to form a bath, anpurifyingthe molten bath and adding suitable ingredients thereto toproduce a, steel of desired composition while subjecting the bath for asuitable period of time to the heat of said deoxidized gas. f

22. The process which comprises forcing a gas comprising carbon monoxidinto a column of iron containing material including an iron oXid todeoxidize the iron oxid and convert carbon monoxid 'to carbon dioxid,adding air' tothel column to form an iron melting'zone, recouvert-in'the carbon dioizid to carbon monoxid, lea ing the carbon monoxid awayafter it emerges from the melting zone,l and causing the same to act`upon an iron oxid to more or lem reduce the same prior to furtherdeoxidation thereof in the column.

23.' The process ofextracting iron' from its ore which comprisesleaching iron ore with sulfuric acid to produce a solution of ferriesulfate, separating the solution from the gangue,"converting the ferriesulfateto an iron oxid, forcing carbon monoxid and air .in regulatedproportions through a column oflmaterial including the iron oXidandcarbon to deoxidize said oXid and melt the deoxidized iron, andutilizingthe sensible heat of the gas resulting from said operation toconvert the ferrie sulfate to ferrie oxid.

24. The process of extracting iron from its ores which comprisesleaching iron cre with sulfuric acid to produce a solution of ferriesulfate, separating the solution from the gangue, converting the ferriesulfate to fai ferrie oXid and sulfur trioxid by the appliim cation ofheat, and heating by the sulfur trioxid.

25. The process for obtaining iron or steel which comprises partiallydeoxidizing the sulfuric acid and conglomerating ferrie oxid. thenmixing lis of the carbon and producinl hot carbon i2@ monoxid gas, andthen collecting the metal as it melts to form a bath subjected to thehot carbon monoxid gas, the carbon monoxid after its action on the bathbeing utilized to effect the' first mentioned deoxida- 12:

tion of the ferric oxid.

26. The process of extractin iron from its ores which comprisesobtaining ferrie sulfate by treatment of the ore, then converting theferrie sulfate into an iron oXid, 13u

then partially deoxidizing and congloinei ating the iron oxid,thenvmixingihe con-y glomeratcd material with carbon and furtherdeoxidizing it in the' Vvpresence of. a;

neutral gas and With partial combustion of the rarbon, ther;v meltingthe iron byfurther combustion ot the carbon and producing hot carbonmonoxid gas, and utilizing the. hot carbon monoxid gas to effect the.first.

mentioned deoxidation ofthe iron oxid, the

sensible heat then left in the gas being utilized to convert the ferriesulfate to an iron.

oxid.

27. The process of extracting iron from its ores wlnchtcomprises.obtaimngferric sulfate by treatment of the ore, the-n converting theferrie sulfate into ferrie oXid,v then partially deoxidizing andconglomer-v ating the ferrie oxid, then mixing the confrlomeratedmaterial with carbon and further deoxidizing 1t in the presento` of adeoxidizing gas and with partial combustion of carbon, then melting theiron by furtherl combustion of carbon and producing hot carbon monoxidgas, and then collecting the ,I

metal as it melts to form a. bath subjected to the hot carbon monoxid,the carbon mony oxid after its action on the lbath being utilized toefectthe hereinbefore mentioned partial deoxidation of theferric o Xiddeoxilation of saidA material.

28.4Tl1'e process of extracting iron from itsA ores which comprisestreating the ore to converty the iron therein into ferric sulfate andseparate it from materials of the ore that are insoluble in sulfuricacid, then converting the ferriel .sulfate t0 f erric oxid, re-

AVVducing the latter, vmelting the iron, and co1- lecting it as itmeltsto form a bath conf ,tinu'ously subjected 'to hea-t and wherein themetal is p-uried.

29. The process of extracting iron from its ores which comprisestreating the ore lto convert the iron therein to an iron sulfate andseparate it from the materials of the ore that are insoluble in sulfuricacid, converting the iron sulfate to an iron oxid, deoxidizing'theoxid,melting the deoxidized iion'gan'd purifying the iron as it melts while,collecting it to form a. bath continuously subjected to heat.r

In 'testimony whereof, I have signed my nameto; this specification.

f aRTHUnlJQMoXHAM.

